An analysis of the molecular structure of active anti-inflammatory agents available in literature suggests that these compounds contain a sub structure of pyridyl group, acid group and sometimes even a sulfur atom.

As for example, compounds like phenylthiomethyl pyridine, Diclonixin, Anpirtoline and Pyridyl carbothiolate contain a pyridyl moiety whereas Anpirtoline and Pyridyl Carbothiolate contain sulfur attached directly to the pyridyl moiety. While looking for some novel anti-inflammatory compound we propose to keep the basic pyridyl moiety intact with change in derivatization pattern on the sulfur and the carboxylic acid group.
From the existing literature it is evident that the compound of interest i.e. the most active compound RS—Z (3-(Pyridin-2-yl sulfanyl)-propionic acid pentyl ester (Ia)) is a new compound not prepared or reported before. Similar compounds or compounds bearing at least thiopyridyl substructure reported in literature are also limited. Following compounds have similarity to the compound of interest here.

But none of these compounds are reported to have any biological activity. Compound (A), i.e. 3-(2-pyridylthio) propionic acid ethyl ester has been reported during the course of study on aromatic substitution (Rossi R A, Pierini A B, Santiago A N, Nucleophilic Aromatic Substitution Organic Reactions 1999, 54, Hoboken, N.J., US), addition reaction of electrogenerated thiolate anion to olefin (Niyazymbetov M E, Konyushkin L D, Niyazymbetova Z I, Litvinov V P, Petrosyan V A. Electrocatalytic addition of thiols to activated olefins. Khimicheskaya, 1991, 260), syn-elimination (Crich D, Lim L B L, J. Chem. Research (S), 1987, 353) and study of SRN1 reaction (Beugelmans R, Bois-Choussy M, Boudet B, Etude des reactions de srn1—parte 10: Action de sulfanions sur les halogenures d'aryle fonctionnalises. Synthese directe de benzothiophenes et thienopyridines Tetrahedron, 1983, 39, 4153). Compound (B), i.e. 5-(2-pyridylthio) pentanoic acid methyl ester is reported in a study on radical reactions (Barton H R, Bridon D, Fernandez-Picot I, Zard S Z, Tetrahedron, 1987, 43, 2733). Compound (C), i.e. 4-(2-pyridylthio) butanoic acid ethyl ester is reported in a study on reaction of 2-trimethylsilylmethylthiopyridine with alkene (Kohra S, Ueda H, Tominaga Y. Reaction of 2-trimethylsilylmethylthiopyridine promoted by a fluoride ion: the first example of generation of 2-pyridylthiomethylcarbanion Heterocycles, 1993, 36, 1497). It was reported some time back that few anti-inflammatory compounds of type phenylthiomethyl pyridine possess biological results (Haviv F, DeNet R W, Michaels R J, Ratajczyk J D, Carter G W, Young P R. 2-[(Phenylthio)methyl]pyridine derivatives: new anti-inflammatory agents. J. Med. Chem. 1983, 26, 218).